skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Selective molecular transport through the protein shell of a bacterial microcompartment organelle

Abstract

Bacterial microcompartments are widespread prokaryotic organelles that have important and diverse roles ranging from carbon fixation to enteric pathogenesis. Current models for microcompartment function propose that their outer protein shell is selectively permeable to small molecules, but whether a protein shell can mediate selective permeability and how this occurs are unresolved questions. In this paper, biochemical and physiological studies of structure-guided mutants are used to show that the hexameric PduA shell protein of the 1,2-propanediol utilization (Pdu) microcompartment forms a selectively permeable pore tailored for the influx of 1,2-propanediol (the substrate of the Pdu microcompartment) while restricting the efflux of propionaldehyde, a toxic intermediate of 1,2-propanediol catabolism. Crystal structures of various PduA mutants provide a foundation for interpreting the observed biochemical and phenotypic data in terms of molecular diffusion across the shell. Finally and overall, these studies provide a basis for understanding a class of selectively permeable channels formed by nonmembrane proteins.

Authors:
 [1];  [2];  [3];  [3];  [1];  [4];  [1]
  1. Iowa State Univ., Ames, IA (United States). Roy J. Carver Dept. of Biochemistry, Biophysics, and Molecular Biology
  2. Univ. of California, Los Angeles, CA (United States). Molecular Biology Inst.
  3. Univ. of California, Los Angeles, CA (United States). UCLA-DOE Inst. for Genomics and Proteomics
  4. Univ. of California, Los Angeles, CA (United States). Molecular Biology Inst. UCLA-DOE Inst. for Genomics and Proteomics. Dept. of Chemistry and Biochemistry
Publication Date:
Research Org.:
Iowa State Univ., Ames, IA (United States); Univ. of California, Los Angeles, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23); National Inst. of Health (NIH) (United States)
OSTI Identifier:
1172992
Grant/Contract Number:  
AC02-06CH11357; 5P41RR015301-10; 8 P41 GM103403-10; R01AI081146; T32-GM008496
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 112; Journal Issue: 10; Journal ID: ISSN 0027-8424
Publisher:
National Academy of Sciences, Washington, DC (United States)
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; microcompartment; protein channel; carboxysome; Salmonella; B12

Citation Formats

Chowdhury, Chiranjit, Chun, Sunny, Pang, Allan, Sawaya, Michael R., Sinha, Sharmistha, Yeates, Todd O., and Bobik, Thomas A. Selective molecular transport through the protein shell of a bacterial microcompartment organelle. United States: N. p., 2015. Web. doi:10.1073/pnas.1423672112.
Chowdhury, Chiranjit, Chun, Sunny, Pang, Allan, Sawaya, Michael R., Sinha, Sharmistha, Yeates, Todd O., & Bobik, Thomas A. Selective molecular transport through the protein shell of a bacterial microcompartment organelle. United States. doi:10.1073/pnas.1423672112.
Chowdhury, Chiranjit, Chun, Sunny, Pang, Allan, Sawaya, Michael R., Sinha, Sharmistha, Yeates, Todd O., and Bobik, Thomas A. Mon . "Selective molecular transport through the protein shell of a bacterial microcompartment organelle". United States. doi:10.1073/pnas.1423672112. https://www.osti.gov/servlets/purl/1172992.
@article{osti_1172992,
title = {Selective molecular transport through the protein shell of a bacterial microcompartment organelle},
author = {Chowdhury, Chiranjit and Chun, Sunny and Pang, Allan and Sawaya, Michael R. and Sinha, Sharmistha and Yeates, Todd O. and Bobik, Thomas A.},
abstractNote = {Bacterial microcompartments are widespread prokaryotic organelles that have important and diverse roles ranging from carbon fixation to enteric pathogenesis. Current models for microcompartment function propose that their outer protein shell is selectively permeable to small molecules, but whether a protein shell can mediate selective permeability and how this occurs are unresolved questions. In this paper, biochemical and physiological studies of structure-guided mutants are used to show that the hexameric PduA shell protein of the 1,2-propanediol utilization (Pdu) microcompartment forms a selectively permeable pore tailored for the influx of 1,2-propanediol (the substrate of the Pdu microcompartment) while restricting the efflux of propionaldehyde, a toxic intermediate of 1,2-propanediol catabolism. Crystal structures of various PduA mutants provide a foundation for interpreting the observed biochemical and phenotypic data in terms of molecular diffusion across the shell. Finally and overall, these studies provide a basis for understanding a class of selectively permeable channels formed by nonmembrane proteins.},
doi = {10.1073/pnas.1423672112},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
number = 10,
volume = 112,
place = {United States},
year = {Mon Feb 23 00:00:00 EST 2015},
month = {Mon Feb 23 00:00:00 EST 2015}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 33 works
Citation information provided by
Web of Science

Save / Share: